Building block and construction model kits are generally either of the type that consist simply of blocks that may be placed one upon the other without connecting means to fasten them together, or of construction units or blocks of various shapes and sizes which are deliberately fastened together by providing, for example, interlocking means which are integral with the construction units themselves, or by strips, pins, nuts & bolts, clamps, etc. which are inserted through preformed holes, grooves, etc. in the building unit itself. These kits frequently only provide the means for constructing a limited variety of models because of the predetermined positioning of holes, grooves, etc. A more serious objection to such toys is the fact that the kits consist of many small connector pieces which are easily lost, or even more seriously, may be swallowed by infants, or perhaps be stepped upon and broken into even smaller pieces, plus the added hazard that the foot or bare foot itself may be injured.
It is also known to form toys, forms or shapes of a non-elastomeric foam composition. However, these items, some of which exhibit a clinging characteristic, do not comply with current safety standards and, in fact, fail upon subjection to required testing procedures.
This invention consists of building units with novel connecting means, made from soft elastomeric foam materials, with no small pieces that might be inserted into a child's eye, ear, nose, or swallowed. The elastomeric foam blocks of this invention meet all safety standards and thus introduce a new order of safety into the field of play blocks and the construction of models and toys associated therewith. My building units also pass the 1977 Consumer Product Safety Commission's "No Choke Test"; whereas some other heretofore mentioned devices are not only very noisy, heavy, slip-and-slide, and fall easily with a "crash", but also contain small, hazardous sub-component parts that fail the above "No Choke Test". My building units have none of these disadvantages.
This new invention provides a safe building unit kit that allows a child to build models representing any real or imagined objects with full exercises of the child's creative abilities unhampered by the restrictions often inherent in the old type building units because of the predetermined connector systems.
The single element building units and blocks of this invention are cut from very large molded blocks or buns of polymeric foams. The polymeric substances used to manufacture the elastomeric foam may be of various types such as esters, ethers, polyols, silicones, and other polymers such as vinyls, etc. I have successfully constructed kits using an elastomeric polyester urethane foam with densities ranging from 0.5 to 10.0 pounds per cubic foot and with elastomeric cell size ranging from 20 to 80 cells per linear inch, and a range of 200 to 400% elongation. In addition, protuberances on the surfaces of this foam material have a very, very significant effect upon the Angle of Repose. I tested equal surfaces and volumes of wood, plastic, and blocks according to this invention with respective densities of 41, 25 and 2 pounds per cubic foot on plate glass and 404 grade stainless steel and found the respective Angles of Repose on both surfaces were 16, 16 and 45 degrees. Thus, the unique production feature of this invention provides considerably more holding power when adjacent to a smooth surface and lends greater design benefits to the creator-builder.
I have found that a foam block with optimum flexibility and elastomeric properties for building units is provided by an urethane polyester type foam with a density of 1.5 to 3.0 pounds per cubic foot; cell size ranging from 40 to 60 cells per linear inch; 225% to 275% elongation and an Angle of Repose of 30 to 50 degrees. Blocks fabricated from a foam of this type also have excellent squeeze/grab properties which make them easy to pick-up and manipulate for both the young and old who need to develop better eye and hand coordination or motor skills.
When a relatively large elastomeric foam building unit of the general type described above is cut to yield smaller building units, all surfaces of each building unit consist of flexible cell-cups. When these smaller building units are placed in contact with one another, the protuberances penetrate into the cell-cups and the building units cling together. Hence, all these building units work in harmony as one unique basic building element without the need of any other auxillary building elements, and as such, no other attachment means are required. There are no limitations to the orientation of building units when constructing a model; all pieces can be utilized in any order or in any orientation as a child creates his or her own objects. The building units may also be formed in an almost infinite variety of shapes and sizes. The building units are preferably assembled into kits of various sizes, and I have found that the best two sizes are the 100 piece set and the 25 piece set, with twelve distinct shapes, in four warm pastel colors.
These sets, in kit form, have reusable capabilities to convert ideas into prototype models, projects, and static toys which allow children's and adults' visions to become realities. For example, children, ages 3 and up, can build such simple items as a house, cross, tee-pee, umbrella, car, church, school, Mom, Dad, chair, shoe, sunrise/sunset, key, clock, animals, truck, cup, tree, etc.
The exterior of the building units with their protuberances and cell-cups is such that they absorb noise and do not generate any noise themselves. We have further found that teachers like the blocks' quietness because an activity with the blocks of this invention and another, unrelated activity can be conducted at the same time and in the same room, without confusion. Also, during the school play periods, if the children should throw the blocks at each other, no one will be injured. Sometimes, when the children appear to have extra energy, the teachers may deliberately allow the children to throw these soft blocks at each other in a fun way without anyone getting hurt, and somehow most of the soft blocks are directed at the teacher which also helps her to learn too! If the soft blocks are stepped upon accidentally, the blocks will not break or injure the foot because they compress and immediately assume their original shape when the compression force is removed.
I have observed that the single element building units with their clinging properties, are particularly attractive for children ages 3, 4, and 5. For older children, adults, and senior citizens, ages 6 and up, another means of connecting building units may be employed. In this advanced block type construction, representing a second exemplary embodiment of the invention, the elastomeric foam blocks with their thousands of interconnecting cells, function as uniform and near invisible perforations to accept simple pins or tubular connector elements in an almost infinite way, and yet when these perforations are not in use they elastomerically snap close. The substance of the elastomeric cell can be utilized to serve as the holding mechanisms for simple connecting pins which are capable of being inserted into the foam cells anywhere on the surface of the block. These simple pins can be solid or tubular, although I have found that the tubular connectors are better than the solid pins because they are lighter in weight, yet stiff enough to be inserted into the foam without bending, and readily secure the units or blocks together.
After it is determined by the creator-builder where the tubular connectors are to be inserted, I have further found that it is easy for a supervising teacher, parent, or grandparent to make a guide hole with a toothpick for example. The toothpick hole will make a pilot hole by breaking through the cellular membranes in a straight line and thereby make it much easier for the larger diameter tubular connectors to be inserted into and through the block and penetrate a second block in contact with the first block deeply enough to join them together. When the pins are withdrawn, the perforations elastomerically snap close.
The preferred length of these tubular connectors ranges from 3.0 inches (to pass the "No Choke Test") up to 15.0". The tubular connectors which I have experimented with range from very thin walled and flexible plastic straw type tubes to more rigid balloon-type polyolefin sticks with an outside diameter of 5/16th of an inch and a wall thickness of 1/16th of an inch. The preferred tubular connectors have a 3/16th inch outside diameter and wall thickness of 1/32th inch and are made of polyolefins, blends of styrene olefins or similar plastics.
From an esthetic point of view, clear tubular connectors are preferred for the children in the space-age mood, whereas multi-color tubular connectors can also be used for a more artistic look. The choice of color is left up to the mind of the creator-builders. This novel method of connecting building units provides a system with unlimited flexibility in the design and construction of objects. No restrictions have been imposed by the system of manufacture. The child is free to follow her or his creative instincts in building any structure that she or he is capable of imagining. Compared to previous systems, my systems encourages a child to create without limitations. The building units may be colored in various ways and the variety of shapes and sizes are without limit, too. In this regard, the invention is not necessarily confined to the specific descriptions in the foregoing disclosure nor is it limited in any way to the specific constructions illustrated and described further herein.